Transcript for The three Republicans vying to be the next senator from McCain's home state

Do not D of our present difficulties. Elieve alwaysthe promise and gatness ofause ING isvitable he The dying wishf senator John M read alou today by his long-t Rick Davis. Ittands in stark contrast to prt trump's handling of long-serving republican'sdeathwee kind. The white house flag lowered to half staff inccain's honor LAN Saturday but raised agn just over hours lat after PC outrage the president did order that flag lower onc again. And thenay -- Mr.esident, any this on johnccain? . President, any thoughts on John McCain? Reporr: ABC news's Jon Karl tried to the presio say something, anythg about McCain. Do youieve J McCain was a hero, sir?won't you S anythinbout John Repr: Final this tonight. Ha for our country. Soha very much. Reporter: The senator was a frequent target for trum even Ng mccainn' a war because here by the H Vietnamese. I L peothat weren't captured. Okay?I have toell you. Reporter: For now McCain's seat will be filled by an appointment from Arizona's governor. But tomorrow voters in mccn's home state will pick the Republican nominee for S being vacated by retiring Republican senateff flake. The candidates include congresswomanartha mcsally, former Sheri Joe arpaio, and dr.elli wa and they ar a far cmccaiyle Republican in fact, they've aechd been outtrump one another for Mo. It's remarkable that none of E candidates oe republin si are looking to be the mccandidate. L of there look Donald Trump's Cante. Sheri arpaio. Reporter:86-year-old sheriff esishment. As the law man for 24 years in maricopa county,rizona's rest and home to the largest city, Phoenix, arpaio opened an arpaio's tent cities mates were dressed in cartoonish black and white striped uniforms a Wes another unconventional that today is framed on the wall of his office. You were hg the M inmatesnk wear. Everybody wears pink. Reporarpaio's methofor punishgminals dre criticism for bei inhumane discriminatory. 1epartmentf justice report paio'sls including hist city were found to have "A pervasive C of discriminatory bias against Latinos." Do you thinkt will Ben issue in the senate camn foryou? No. Because I'm running statewide. There are a of hispanics through Not THA many. Reporter: About Arizona's population is hispanic. It is a fastwing par the population and a critical vote. You can't alienate a whole ic group in Arizona and expect to become theisenar. 2017 arpaio was convict criminal cont of court for federaljudgs order to stop racirofiling in detaining individuals suspe O being in the U.S. Arpaio disputes that conviction calling it witch hunt by the formerttgeneral, a conspiracy to bring you down Yeah, aracy. Involving the courts, involving the departm of justice. Involving obamt is the proof? I'm not guilty. That's the proof. Reporter: Last year, one month after his conviction, president trump pardoned arpaio. Is the fact T trs in office in the white house, is that part O why you want to go tohington a this moment? Let M putt this way. If HSN't the est, ire would not be F senate. Are you sad that the tent cies aregone? I know it was aat progm. But you know, the sheriffanymore. I'm trying to get down to Washington and try to straight some problems out.pecially in the jial stem. But is that about going T Washington for payback? No going to Washington Tak a difference. Alsoabrd the trump train one of John mn's rmer political adversaries. Kelli ward, who ran against lat senator in the Republican primary I 2016. Do you think T has had a impact on P here? Ink that Donald Trump the mantle as the lead republica party has been good inarizona. It's introduced a L of people that before would consider being a repuan. Eporter: People like moniquestockett. T this time we're doing the freescreening. I'm andependent, but I voted mostly Democrat and I voted for oba twice. Twice. And I was listen to Donald um talking and I S did he just say that? I was like so impressed his honesty. I Waser into politics. I had idea how corrupt it is until iot invol because of trump. Saw him on TV going down the escalator with his wife,nd I'm like, yes, that's next president. Reporter: Stockette and her fr run a meetup group support candidates out of Larsen home in Tu What are weo do for the raf snlhave to R something to raise money I have a birdhouse. It's patriotic colors. The number one thing that I Lili supports trump's agenda100%. She is not afraid to sayhat she suppo trump, which a lot of republins don't want to do. I that I'm anti-estabnt. I think that it's -- people wan nebloodn Washington, D.C. Reporter: Ward has a collection O hh-profile and controvers supporrs. Raclly charged have sparked e.dana Rohrabacher, the calif congss who has long curried favor withssia.d Sebastian Gorka, the former ump aide who allegedly has ties to a Nazi oup. She also has backing from the mercer family, the pri uber-wealthy conservative donorswhso pumped money io Donald Trump's 2016 psintial campaign. I mean, I have a gre relationship with the merc an'm very grateful to them R helping me along the political process. Irying to motivate the type of voterhatnkly showed up for D trump two years T may have noinous elections. Eporter: Juspast weekend ataffer for ward publicly impl that the might be some sort of in the timinf main's announcement that he was discontig treatment. In a now deletedebookpost. I wonder if it's coincidence McCain releais statement kickoff day of kelliward's bus tour or if it S a pto take media atten off her campaign.rdself replying I their comments, "I they wanted to a particular narrative that they hope is negative me." At a press conference today ward addrd comments Tar my comments were in no W directedor mcca O a his ly Reporter: Congresswoman ha mcsally seems to be the favorite to win tomorrow the former fighter lot, the first female to in combat, in fact, inc esement from trump in her campaign. My friend Martha mcsally. She'she deal. She's tough. Csally Tur down multiple requests from ABC news for an terview. Just weekends into the T presidency colleague matttman was right there for O of her packed and very contentious town hall meetings. Lots O folks saying that tho be hear they ar not beinheard, that's why they're here, and the mounting frustration is that they're stuc outside. Reporter: Heronstituent askeder to answer for the president. If people want to take their frustrations with president O me, even -- that is T my role. Reporter: Whoever wins tomorrow will ly face the Democrat Kristen cinema in november.cinema is an Arizona co would the first openly Xu U.S. Senator. Don't unst the STAs here. This race be a referendu well impact who controls the levers of P in waington. Repubcad the senate only two S. If Republicans losearizona,suddenly TRE's a path to the mocrats ctrng the senate. If they hold on to Arizona, then there'mo no way that Democrats able to take control of the senate.

This transcript has been automatically generated and may not be 100% accurate.

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